Disc brake conversion question

[chewychevy67]

Has anybody ever done a disc brake conversion and used a 67 70 Camaro valve like this set up? I am finished all my brake lines and don't want to redo them. This would be easier to plumb in.

[davepl]

I'm lost, that's a master but I don't know what the valve next to it is any why you'd want one.

Are you disc/drum or disc/disc? Is that the master you're running?

[chewychevy67]

It's a porprtioning valve for early disc brake cars. Here is more info. http://www.superchevy.com/how-to/bra...ke-conversion/

[chewychevy67]

And I am doing disc front rear drum. Mcgaughys kit

[RichardJ]

OK, you provided the link, but did you read or fully understand what the guy was trying to tell you?
Actually, it really isn't your fault. The guy did a piss-poor job of what he was attempting to explain.

He was clear about one thing. Everything, anyone sees connected to a brake system is immediately, INCORRECTLY labeled as a proportioning valve.

The item you have there is a Metering Valve. It also goes by the name, Hold-off Valve. It connects to the front brake system only, but after the Warning switch.

The article was trying to explain that in 1967, disc brake systems used several different and separate devises to make the brakes work properly.

In addition to the Dual MC they used a Differential Pressure Warning Switch PLUS Metering Valve PLUS a Proportioning Valve. Three different items with different jobs to perform.

Your first picture has a Dual MC sitting on top of a Pressure Warning Switch and a Metering Valve. You still need a Proportioning valve.

The article also explains that the three items were replaced with a Combination Valve in most cars by 1970.

The non-adjustable, standalone Proportioning Valve were usually mounted on the frame near the rear of the car. Not sure why. Chrysler used the same valve and also mounted it near the rear. Most people don't know it's there or what it is.

A Combination Valve would include everything you need.

Wilwood sells an adjustable Proportion Valve, that includes the Switch. Add your Metering Valve to the Wilwood and you have a complete system

[chewychevy67]

Yes I get that. I guess what I wanted to know is if I have a stock power drum drum 67 gmc and I add the 6 lug mcgaughys disc kit can I add the hold off valve that sits mounted to the master cylinder used on 67 to 70 cars with factory disc brakes to my already existing master cylinder and metering valve and have the brakes work properly. I could go get the 71 and up lines and prop valve but all of my brake lines are in and new. If I have to mess with them I will just keep the stock power drums.